2 posts were merged into an existing topic: Woman driven to violence by Country music
Cleaned up the thread 
Thanks for the inputs on this,
I tried to upgrade my vega to 256 but the āprogramā is ended as Wang told me so no upgrade for my Vega
in ht either side i have been reading that upgrading to DSD512 is something quite better that being upgrading at dsd256
So i think i will sell
Kind regards
Some nice review from AudioStream, I agreed listening in NOS mode is what makes this DAC so unique from the rest. Considered the price range, it is simply hard to find one that comes close.
Googling has failed me, does anyone know where one can get one of these in Europe. The DAC looks very interesting and not hyper-expenisve as these things go.
.sjb
I just got myself a Level 3! For my birthday.
Oh waitā¦ my birthday is in January 
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Not sure about EU, but I got mine from Wildism Audio in HK. His quote is reasonable and ship worldwide.
Haha! Need to get a quote from himā¦
@Sloop_John_B you can buy them in The Netherlands. I am not annyway connected to Them. http://www.magnahifi.com/index.php/nl/webshop/product/holo-audio-spring-dac-level-2-red-label-r2r-dsd
it is a trusted shop amoung dutch audiophiles and one of the sponsers of a dutch audiophile forum. So you should be good 
Hope this helps
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Has anyone compare the SQ difference between hardware OS in Holo Spring (AK4137) and Roon 1.3 up sampling in the following.
- Holo Spring (set OS ) of 44.1k source vs Roon 1.3 up sampling to 352.8k(set Holo Spring to NOS)
- Holo Spring 44.1k to DSD256 (set OS DSD) vs Roon up sampling 44.1k to DSD256 (set Holo Spring to NOS)
I havenāt done that yet Guy, but might try it this weekend. Iāve never played music through the OS section of the Spring though, so it might need to break in ! NOS all the way here.
also very interested in the Spring, and how it performs with the OS of Roon.
A friend and I compared the Roon OS with the native OS of his Audio-GD DAC19, and here we found the OS of the Audio GD markedly better, to our surprise (we expected the Roon OS to be better due to more processing power being available through the Roon server).
For anyone interested, we tested like this:
Roon without OS -> Audio-GD with OS enabled -> amp,
vs Roon with OS -> Audio-GD with OS disabled -> amp.
Tried both maximum and 2x maximum on Roon.
It would be interesting to see Roon with OS -> Audio-GD with OS enabled -> amp with maximum on Roon. In theory it should sound the same as your case 2 butā¦
PCM or DSD? One thing to keep in mind is that oversampling involves a digital filter, since the new samples are underdetermined by the original ones (IOW, there are many ways of interpolating between the given samples, and those ways correspond to different filters/smoothers/regularizers ā choose your lingo according to your training ;)) So, itās not surprising that Roonās and Audio-GDās sound different. If you read up on digital filters for oversampling, you quickly descend into a maze of twisty little passages called āminimum phase,ā āclosed form,ā ātime-domain optimization,ā ā¦ I sort of semi-understand some of them (applied math/CS background, not EE/DSP), but Iām sure thereās a lot I donāt. Personally, Iām fond of the closed-form Schiit filters that to my ears do a great job on 44.1/16 PCM material. But Iām waiting for my Spring to compareā¦
How do you oversample on Roon?
I think, the proper term is āup samplingā, which is normally used in software (PC) while āover samplingā refers to the internal DAC chip that does over sampling plus digital filter, hence, the word, over sampling digital filter is a common word associated with DAC.
We tested PCM.
By the way, I just saw the new Roon release, and even on bluetooth headphones (with some compression), I can hear a marked improvement. Things may have significantly changed now, and I hope we can compare again soon.